Package com.google.common.collect

Class ImmutableSet<E>

java.lang.Object

java.util.AbstractCollection<E>

com.google.common.collect.ImmutableCollection<E>

com.google.common.collect.ImmutableSet<E>

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<E>, java.util.Collection<E>, java.util.Set<E>

Direct Known Subclasses:

ImmutableEnumSet, ImmutableMapEntrySet, ImmutableSet.Indexed, ImmutableSetMultimap.EntrySet, ImmutableSortedSetFauxverideShim, SingletonImmutableSet

@GwtCompatible(serializable=true,
               emulated=true)
public abstract class ImmutableSet<E>
extends ImmutableCollection<E>
implements java.util.Set<E>

A Set whose contents will never change, with many other important properties detailed at ImmutableCollection.

Since:

2.0

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ImmutableSet.Builder<E>	A builder for creating ImmutableSet instances.
(package private) static class	ImmutableSet.Indexed<E>
private static class	ImmutableSet.SerializedForm

Nested classes/interfaces inherited from class com.google.common.collect.ImmutableCollection

ImmutableCollection.ArrayBasedBuilder<E>

Field Summary

Fields

Modifier and Type	Field	Description
private ImmutableList<E>	asList
private static int	CUTOFF
private static double	DESIRED_LOAD_FACTOR
(package private) static int	MAX_TABLE_SIZE

Constructor Summary

Constructors

Constructor	Description
ImmutableSet()

Method Summary

Modifier and Type	Method	Description
ImmutableList<E>	asList()	Returns an ImmutableList containing the same elements, in the same order, as this collection.
static <E> ImmutableSet.Builder<E>	builder()	Returns a new builder.
(package private) static int	chooseTableSize(int setSize)	Returns an array size suitable for the backing array of a hash table that uses open addressing with linear probing in its implementation.
private static <E> ImmutableSet<E>	construct(int n, java.lang.Object... elements)	Constructs an ImmutableSet from the first n elements of the specified array.
static <E> ImmutableSet<E>	copyOf(E[] elements)	Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source array.
static <E> ImmutableSet<E>	copyOf(java.lang.Iterable<? extends E> elements)	Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source iterable.
static <E> ImmutableSet<E>	copyOf(java.util.Collection<? extends E> elements)	Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source collection.
static <E> ImmutableSet<E>	copyOf(java.util.Iterator<? extends E> elements)	Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source iterator.
private static ImmutableSet	copyOfEnumSet(java.util.EnumSet enumSet)
(package private) ImmutableList<E>	createAsList()
boolean	equals(java.lang.Object object)
int	hashCode()
(package private) boolean	isHashCodeFast()	Returns true if the hashCode() method runs quickly.
abstract UnmodifiableIterator<E>	iterator()	Returns an unmodifiable iterator across the elements in this collection.
static <E> ImmutableSet<E>	of()	Returns the empty immutable set.
static <E> ImmutableSet<E>	of(E element)	Returns an immutable set containing element.
static <E> ImmutableSet<E>	of(E e1, E e2)	Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified.
static <E> ImmutableSet<E>	of(E e1, E e2, E e3)	Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified.
static <E> ImmutableSet<E>	of(E e1, E e2, E e3, E e4)	Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified.
static <E> ImmutableSet<E>	of(E e1, E e2, E e3, E e4, E e5)	Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified.
static <E> ImmutableSet<E>	of(E e1, E e2, E e3, E e4, E e5, E e6, E... others)	Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified.
(package private) java.lang.Object	writeReplace()

Methods inherited from class com.google.common.collect.ImmutableCollection

add, addAll, clear, contains, copyIntoArray, isPartialView, remove, removeAll, retainAll, toArray, toArray

Methods inherited from class java.util.AbstractCollection

containsAll, isEmpty, size, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream, toArray

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface java.util.Set

add, addAll, clear, contains, containsAll, isEmpty, remove, removeAll, retainAll, size, spliterator, toArray, toArray

Field Detail

MAX_TABLE_SIZE

static final int MAX_TABLE_SIZE

See Also:

Constant Field Values

DESIRED_LOAD_FACTOR

private static final double DESIRED_LOAD_FACTOR

See Also:

Constant Field Values

CUTOFF

private static final int CUTOFF

See Also:

Constant Field Values

asList

private transient ImmutableList<E> asList

Constructor Detail

ImmutableSet

ImmutableSet()

Method Detail

of

public static <E> ImmutableSet<E> of()

Returns the empty immutable set. Preferred over Collections.emptySet() for code consistency, and because the return type conveys the immutability guarantee.

of

public static <E> ImmutableSet<E> of(E element)

Returns an immutable set containing element. Preferred over Collections.singleton(T) for code consistency, null rejection, and because the return type conveys the immutability guarantee.

of

public static <E> ImmutableSet<E> of(E e1,
                                     E e2)

Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified. That is, if multiple elements are equal, all except the first are ignored.

of

public static <E> ImmutableSet<E> of(E e1,
                                     E e2,
                                     E e3)

Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified. That is, if multiple elements are equal, all except the first are ignored.

of

public static <E> ImmutableSet<E> of(E e1,
                                     E e2,
                                     E e3,
                                     E e4)

Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified. That is, if multiple elements are equal, all except the first are ignored.

of

public static <E> ImmutableSet<E> of(E e1,
                                     E e2,
                                     E e3,
                                     E e4,
                                     E e5)

Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified. That is, if multiple elements are equal, all except the first are ignored.

of

@SafeVarargs
public static <E> ImmutableSet<E> of(E e1,
                                     E e2,
                                     E e3,
                                     E e4,
                                     E e5,
                                     E e6,
                                     E... others)

Returns an immutable set containing the given elements, minus duplicates, in the order each was first specified. That is, if multiple elements are equal, all except the first are ignored.

Since:

3.0 (source-compatible since 2.0)

construct

private static <E> ImmutableSet<E> construct(int n,
                                             java.lang.Object... elements)

Constructs an ImmutableSet from the first n elements of the specified array. If k is the size of the returned ImmutableSet, then the unique elements of elements will be in the first k positions, and elements[i] == null for k <= i < n.

This may modify elements. Additionally, if n == elements.length and elements contains no duplicates, elements may be used without copying in the returned ImmutableSet, in which case it may no longer be modified.

elements may contain only values of type E.

Throws:

java.lang.NullPointerException - if any of the first n elements of elements is null

chooseTableSize

static int chooseTableSize(int setSize)

Returns an array size suitable for the backing array of a hash table that uses open addressing with linear probing in its implementation. The returned size is the smallest power of two that can hold setSize elements with the desired load factor.

Do not call this method with setSize < 2.

copyOf

public static <E> ImmutableSet<E> copyOf(java.util.Collection<? extends E> elements)

Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source collection.

Performance note: This method will sometimes recognize that the actual copy operation is unnecessary; for example, copyOf(copyOf(anArrayList)) will copy the data only once. This reduces the expense of habitually making defensive copies at API boundaries. However, the precise conditions for skipping the copy operation are undefined.

Throws:

java.lang.NullPointerException - if any of elements is null

Since:

7.0 (source-compatible since 2.0)

copyOf

public static <E> ImmutableSet<E> copyOf(java.lang.Iterable<? extends E> elements)

Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source iterable. This method iterates over elements only once.

Performance note: This method will sometimes recognize that the actual copy operation is unnecessary; for example, copyOf(copyOf(anArrayList)) should copy the data only once. This reduces the expense of habitually making defensive copies at API boundaries. However, the precise conditions for skipping the copy operation are undefined.

Throws:

java.lang.NullPointerException - if any of elements is null

copyOf

public static <E> ImmutableSet<E> copyOf(java.util.Iterator<? extends E> elements)

Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source iterator.

Throws:

java.lang.NullPointerException - if any of elements is null

copyOf

public static <E> ImmutableSet<E> copyOf(E[] elements)

Returns an immutable set containing each of elements, minus duplicates, in the order each appears first in the source array.

Throws:

java.lang.NullPointerException - if any of elements is null

Since:

3.0

copyOfEnumSet

private static ImmutableSet copyOfEnumSet(java.util.EnumSet enumSet)

isHashCodeFast

boolean isHashCodeFast()

Returns true if the hashCode() method runs quickly.

equals

public boolean equals(@Nullable
                      java.lang.Object object)

Specified by:

equals in interface java.util.Collection<E>

Specified by:

equals in interface java.util.Set<E>

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Specified by:

hashCode in interface java.util.Collection<E>

Specified by:

hashCode in interface java.util.Set<E>

Overrides:

hashCode in class java.lang.Object

iterator

public abstract UnmodifiableIterator<E> iterator()

Description copied from class: ImmutableCollection

Returns an unmodifiable iterator across the elements in this collection.

Specified by:

iterator in interface java.util.Collection<E>

Specified by:

iterator in interface java.lang.Iterable<E>

Specified by:

iterator in interface java.util.Set<E>

Specified by:

iterator in class ImmutableCollection<E>

asList

public ImmutableList<E> asList()

Description copied from class: ImmutableCollection

Returns an ImmutableList containing the same elements, in the same order, as this collection.

Performance note: in most cases this method can return quickly without actually copying anything. The exact circumstances under which the copy is performed are undefined and subject to change.

Overrides:

asList in class ImmutableCollection<E>

createAsList

ImmutableList<E> createAsList()

writeReplace

java.lang.Object writeReplace()

Overrides:

writeReplace in class ImmutableCollection<E>

builder

public static <E> ImmutableSet.Builder<E> builder()

Returns a new builder. The generated builder is equivalent to the builder created by the ImmutableSet.Builder constructor.